Abstract

The properties of a small pancake coil made with a wide copper-stabilized (YBCO)coated conductor were investigated. The radial component of the magnetic field was mapped at the coil edge in both the dc and ac regimes and differs significantly from that calculated assuming a uniform current distribution. The observed hysteresis indicates the strong influence of the ferromagnetic properties of the substrate. The ac losses of the coil were measured for ac frequencies between 60 and . The differences in properties of the YBCO coil and a similarly prepared copper coil are discussed.